Safety device for flat-bed printing presses



9* P. COLQUHOUN SAFETY DEVICE FOR FLAT BED PRINTING pREssEs F 119 a h 1925 3 Sheets-Sheet 1 I JA/I/EA/TQZ? Z ,Zq I f. K I

TOWA/E; $45

9 Q Aug 7 P. COLQUHOUN SAFETY DEVICE FOR FLAT BED PRINTING PRESSES Filed March a, 1925 a Sheets-Sheet 2 I H Tra 7-?5 vs Aug. 9, 1927 w P. COLQUHOUN SAFETY DEVICE FOR FLAT BED PRINTING PRESSES Filed March 9. 1925 5 Sheets-$heet 3 4% Kim Patented Aug. 9, 1927.

PETER COLQUHOUN, F oLEvELANnoHIo, Asslenon To THE AMERICAN MULTI- GRAPH colvrrAnY. 0F CLEVELAND, c1510, AconronArIoN OF OHIO.

SAFETY :onvicn on FLAT-BED rnrnrrnernnssns.

Application filed March 9, 1925..Seria1 No'. 14,123; d

ing the platen would result in fouling thetympan sheet of the cylinder against the inked type. v The general object of the invention isto provide a printing mechanism which: shall be etficient and rapid in its operation and in which the operating parts are protected against accidental actuation at any improper time by safety mechanisms.

In the printing press shown in the drawings the type is contained in a flat chase reciprocable beneath a rotating cylinder or impression platen on which a sheet of paper.

is carried into engagement with the'type.

The paper is printed during the reciproca-- tion of the type bed in one direction; while 30, the cylinder or platen continues to rotate to eject theprinted sheet from the machine during, the return travel of the type bed.

Such a press is shown, described and claimed in r the application of Lawrence Morse, Serial'No. 602,161 filed November 20,

1922 and in the application of Henry C.

Osborn, Ser. No. 616,924 filed Feb. 5,1923. Reference should be made to the latter application in regard to paper controlled,

40 latch-operating mechanism herein shown but not claimed, whereby themovement of.

' the paper as it is drawn by the platen towards the type bed causes the actuation of mechanism I which lowers the impression platen into engagement with the type.

In the'drawings, Fig. 1 is a plan view ofa printingpress in connection with which my invention is adapted to operate, certain portions including the paper feeding-tray,"

the inking mechanism and the paper receiv-' ing tray, being removed as inessential to the operation of my invention; Fig. 2 is a'fragnientary side elevation of the central portion of the printing press; Fig. 3 is a similar side elevation showing the parts in different-posithe general frame of'the machine is shown vat 1, whichframe may be adapted to supwmechanism adapted to cooperate with. a

tion; Fig. 4' is a similar side elevation showing the-parts in still another position; Fig.

5 is a fragmentary cross section through the" paper feeding mechanism and showing a portion of the printing cylinder or platen in end elevation. 7 q

Referring in detail to the drawings and indicating the various'parts by numerals,

port the power'mechanism and reciprocatinggearing (not shown) .for the type. bed. The frame has flanges 2 at either side which support side frame members 3, and 4 in which is journalled the shaft 5 forv the im-; pression platen 6. The platen is arranged to be rotated by a gear 7 shown at the left of the macl1ine'inFig.*1, which may be con nected by an Oldham coupling (not shown) to one end of the shaft 5 ofthe platen. The gear"; is operated in timed relation tothe reciprocation of a type bed 10, which may be driven as shown in the prior application of pMorse above referredto or in any manner.

The timing of the rotationof; the platen and .30

the reciprocation of the type bed is'such that the platen rotates twice to every complete (that is forward and backward) reciprocation of the bed, and it may be assumed that the type is inked by suitable ink ink fountain at one end'of the, stroke of the. ty e bed.

ylnvention consists a safety latching 190 platen retaining latch for holding the platen or printing cylinder in lowered or type engaging position and with an auxiliary latching mechanism which cooperates with the first mentioned latch to hold fit-in inoperative positionwhen no paper is being fed. This retaining latch for the printing cylinder comprisesa plate 20 rigid on one end of the platen shaft and arranged to be. turned with relation to the frame, byja link 21 and 1 0 arms 22 and 23 rigidly secured to a rock shaft 24 journalled in the side frame .member 3/ The shaft has an eccentricport-ion 25 as shown in Fig. 2whic'h causesthe raising and lowering of the platen whenever the 0 2 plate 20 is partially rotated. The position of the plate when the platen is lowered corresponds to Fig. 2, while the unlatched idle position is thatshown in Fig. 3. 4 For lowering theplaten, I make use of the :8 feeding mechanism such. as rollers and an reciprocating movement of the type bed, and for rarsingit, I may employ a spring 30 con- -necting the plate with the frame 1. For

holding the'platen in its lowered or prln'tmg, i I i I I stop fingers from the path oi the paper by a 7 posit-ion I: have shownan abutment 35 car ried by the plate 20 whichis engaged by the forward end oi alatch 36 normally held downward in plate engaging position by a link 37 connected to a bell-'crank38hthe lower" of the plate? Tl ese pins coact .witli the lever 23 and with cam members supportedby the bed plate during a certain portion of their movement as will be later described.

For holding the latch 36 normally out of engagement with the plate 20 and allowing the spring to raisethe platen into inactive position, I employ an auxiliary latching lever having ashoulder 60 adapted to en gage a notch 61' in the latch 36. The lever '59'is' normally held in engagement with the latch by reason of a tension spring 62 and, when a sheet is fed to the platen, the arm 59 is rotated to theright as shown in Fig.2 to allow the latch 36 todrop into engagement with'the' abutment holding the platen in lowered position. This occurs just after the type bed has reached its rearmost position and is returning forwardly beneath the platen. At this time, a pivoted cam cat: ried by thetype-bed cams upwardly on a roller 46 carried byfthe arm 23 to rock the plate 20 and lower the platen.

I A convenient method of feeding paper to.

the platen is that shown and claimedL in a copending application of Lawrence Morse, Serial 1%,013', filed March 9th, 1925. This method includes mounting paper tray such as shown at in front of the ma-' chine, and paper may be fed by hand therefrom a sheet at a time as shown in Figg5 against stop fingers 71 pivotally mounted in normally-rigid frame arm members 72- and 73. These fingers rise in timed" relation with the rotation of- ,the platen, and a pairof 'friction rollers' 7e and 75 (one of'which is continuously driven) drive the paper for- I ward into engagement with the platen and beneath the upraised fingers. The stop fingers androlls may be operated by a two-to- "one gearing comprising gear members 78 gear 7 9 carries cams 80 and 81 the'latter act- "ingto lowe r the roller 74 to compress the paper betweenit and the roller 7 5 through arms 83 and '84. The former of these 'arms ter by a rock shaft 85 which supports the' roller carrying armsSG. This rocking movement of the shaft 85 also acts to raise the lever which engages a lug the stop lingers. 1 v V 0 Suitable mechanism for gripping the forward edge of the paper may include gripper,

91' rigid with lingers actuated by and sector mechak J nism 94 and 95 which is in turn operated by a cam 96 rigid with the frame against which a roller 97 on the sector normally bears."

The cam is so shaoed that the fingers o 3811 at "various points when the platen cylinder rotated with reference to the trams In the pos'ition'shown in Fig. 2, the fingers are shown as having engaged the forwardedge of the paper and as carrying it around the platen into aposition to be printed, and in Fig. 5 the fingers are shown, in position about to open to eject the printed sheet.

The mechanism which I have shown for causing the: movement of thefpaper when drawn by the platen gripper fingers to cause the auxiliary latch 59 to disengage the latch 36, when the platen is lowered, is substantially that shown and claimed in the Osborn application above referred'to. 'As the paperis drawn around the platen the cam 80 on the two-to-one gearingv operates through an arm 100, rock shaft; 101and. a

tripping of the auxiliary latch 59, allowing the latch 36 to operate to hold the platen in lowered position. The movement of theroller 103 is translated through an eccentric =disc'105 on the end of the shaft"108 tothe upwardly extending arm or the lever 59,

carrying it forwardly to the position shown in Fig. '2 to release the latch 36. Thisreleasing occurs'only-once foreach double totation of the "platen. ()rdinarily the platen cannotbe rotated to its lowered position by the engagement of the cam 45' with the roller on the arm 23' when no paper is fed to the machine because the cam is held" up by the pinl when theoarriage. s adjacent its extreme left hand-position; but. if 7 an accidental tripping of the latch 59 a lowed the latch 36 to drop into engagement with.

the abutment 35 on the plate 20, this would withdraw the pin-41 and allow the cam-to drop with the resultthat the tympan sheet would'b'e brought into direct contact with i the inked type. This would result in subsequentoffsetting of the wet ink on the tymp'an sheet to the back'of the paper next to the right as shown in Figure 4 while the roller on the arm 23 is being returned to its lowermost position by a cam31 on the rear end of the type bed. A rise 32 on an overhanging cam member 33 ordinarily acts through a projection. 3% on the plate 20 to cause the front end of the latch 36 to be forcedup into engagement withthe latch 59 at the end of the forward stroke of the type bed. But if the latch :59 is withdrawn as mentioned so that the latch 36 may im mediately drop down again, the roller on the arm 23 will bump against the cam surface 31 suddenly stopping the machineand perhaps resulting in serious breakage.

The provision whereby I have eliminated these possibilities forms the subject of this invention and the means includes a'locking bar or lever 110 pivoted at 111 to the side frame member 3, which lever normally swings by gravity into the path of an abutment member 113 on the latch 36'. TWhen the latch 59 is in, its active position, as in Fig. 3, thelever 110 does not quite touch the abutment, wherefore the lever may return again to its initial position, when raised, as will be presently described. The forward end of the bar 110 is bent as shown in Fig. 1 at 112 to underlie the rearward end of one of the arms 102,and these arms are depressed once for each paper feeding rotation of the platen by the two-to-one gearing and the cam carried thereby is at this time only momentarily raised fromengagement with the abutment member 113. Thus if paper is fed and the paper friction roller 103 actuated, the lever 110 is moved'out of the WitO'f the abutment on the latch 36 and the latter may function to hold the platen down into active position as shown in Fig. 2. The likelihood of the auxiliary latch 59 being tripped accidentally at this time is very slight and even if it were no more serious damage would ensue than inking the tympan sheet.

The position of the lever 110 is such-that it is for the greater part concealed and it would be extremely unlikely for the operator orany one unfamiliar with the machine to tamper therewith and to cause the untimely operation of both the latch 59 and the lever. If either is operated alone to rev lease the latch 36 its operation is effectively counteracted by the other.

Tclaim: v 1. The combination with a printing couple, of two latching devices either of which is effective to control the coaction of the couple, one of said latching devices being manually operable, the other being inaccessible for manual operation. a

2. The combination with a type bed and cylinder, of a retaining latch for the cylinder, two latching mechanisms cooperating with the retaining latch and either adapted bination witha platen retaining releasable at any time,

- eating bed 'tinuing such position,

to prevent the operation of .the retaininglatch',one of said latchingmeehanisms being accessible for. manual operation and the other inaccessible. I

In a bed and cylinder press, the com-- latch, of

two latching devices coacting therewith, one 7 of said latching devices being'm'anually op.- erable, the other being inaccessible for main ual operation, and mechanism coacting with the paper for operating both of said latching devices. I

a. The combination with a printing couple adapted to be. inactive,. of two latching mechanisms either of-which'is effective to control the coaction of thecouple, inechanism coacting with the paper and adapted to control one of said latching mechanisms.

5. In a safety device for bed and cylinder printing" presses, the combination. withna platen retaining latch, of a. safety latch adapted to preventth-e release of the platen retaining latch, an auxiliary: latch also adapted to prevent the release of the platen retaining latch, and a device for testing'for the presence or absence of'paper cooperating withthe safety latch. I i

6. The combination with, a'bed'and cylin derpress, of retaining latch mechanism adapted to insure operation, two latching mechanisms cooperating with said retaining latch mechanism and either efieetive to prevent the release thereof, paper testing mechanism coacting with the two latching mechvanisms and adapted to move them both when the paper is present, one ofv said latching mechanisms being also manually operable.

7..The comb-nation with a printing couple, retaining means for latching one of the members thereof in'coaction with the other, two latching mechanisms cooperating with said retaining means, one jof said latching mechanisms being periodically released automatically, and the other being manually whereby theinoppor- .tune release of' effective. I a 1 8. In a printing press of the bed and cylinder type, the combination and a rotary platen adapted to coact with the bed or clear it, of a latch. mechanism to retain .theplaten in active pohe later mechanism is 111- Y Y with a recipro-a" sition, an auxiliary latching mechanismco the retaining latch mecha" a safety latching mechanism.

a bed and cylini der, of means for moving the cylinder to active position, a retaining latch. for conan intermediately pivoted bar for preventing the operation of when said mechanism moves down toward flu -ple, positively actingmeane the members of the couple together, a latch mechanism adapted when released to allow the" operation of said the paper to engage it. 7

10. The 'COIfiblllLtlOIl of a printing coufor bringing positively acting means, and mechanism to prevent release of the latch mechanism and thereby prevent said means from'operating.

-11, In a bed and cylinder press, the combination of a reciprocating type bed, a rotary platen adapted to be lowered into coaction with the type bed or raised therefrom, a cam on the type bed, and mechanism operable thereby for positively lowering the platen, a latch mechanism adapted when restrained to hold the cam in idle position and thereby prevent the lowering of the platen, and mechanism to prevent release of l the latch mechanism and thereby prevent the cam from operating.

In a bed and cylinder press, the combination of a reciprocating type bed, a rotary platen adapted'to be moved into coaction with the type bed or moved therefrom,

a cam on the type bed, mechanism operable thereby for positively moving the platen to active position, a latch mechanism adapted when released to retain such position of the platen, and two latching mechanisms to prevent release of the latch meehanisminen- .tioned, one of said lastnamed latching mechanisms operating automatically at a definite time and the other operable manuallyv at':1n definitetnnes i 13. In a bed and cylinder press, the com bination of a reciprocating type bed, a romechanism, and mechanism coacting. with the paper to operate'one of said devices, that one being manually operable and the'other inaccessible for manual operation. In testimony whereof, I hereunto affix my signature.

PETER COLQUHOUN. A 

